using System.Globalization;
using System.IO;

namespace Aespa
{
    internal class Mundo
    {
        public static void main(string[] args)
        {
            string Get_Ids(int[] arr)
            {
                return string.Join('.', arr);
            }
            string name = "RogeAustine";
            int[] arr = { 1, 2, 3 };

            string ids = Get_Ids(arr);
            Console.Write(ids);

            // string.Concat()
            string try1 = string.Concat("Ilove", "Haewon", "andBae");
            Console.Write("\n" + try1);

            // Reference
            // ??????????????
        }
    }
}